Heat transfer characteristics of Cu-MXene/water nanofluid through a triangular channel with k–ε turbulence effects: Applications in energy storage systems

This study numerically investigates the thermo-hydraulic performance of Cu–MXene/H 2 O hybrid nanofluid flowing through a two-dimensional triangular corrugated channel, a configuration highly relevant to high-performance heat exchangers and thermal energy storage systems in internal flows. Using the standard k–ε turbulence model in ANSYS-FLUENT, flow and heat transfer characteristics were analyzed for Reynolds numbers ranging from 5000 to 10,000. Thermophysical properties for nanoparticle weight concentrations of 0.025% and 0.05% were incorporated based on experimentally validated data at 303 K. Results indicate that increasing nanoparticle concentration significantly enhances thermal performance; improvements in the average Nusselt number of 15.22% and 20.02% were observed for 0.025 wt.% and 0.05 wt.% concentrations, respectively, compared to the base fluid. While the friction factor increased by approximately 14–16% for the 0.05 wt.% concentration due to enhanced viscosity, the performance evaluation criterion remained above unity for all cases, reaching a maximum of 1.18 at Re = 10,000. These findings demonstrate that the dual mechanism of triangular corrugations and hybrid nanoparticles effectively disrupts boundary layers to improve heat transfer, outweighing the associated hydraulic penalties. The integration of Cu + Mxene/H2O hybrid nanofluid volume fractions of 9.18%, 19.02%, 25.075%, along with 0%, 0.025%, and 0.05%, resulted in a notable improvement in the heat transfer coefficient of the hybrid nanofluids.